I'm working on a product that uses SN65HVD234 for the CAN bus, but a number of devices in the current lot have very large numbers of CAN errors. We've had quite a few lots where we didn't notice this happening, so it seems like previous devices haven't had this problem, or it has at least been less severe. I've found that adding a small amount of capacitance on the Rs line fixes the problem, but I'm not sure that I have a good explanation of what's going on, so I'm hesitant to implement it until I know more. Our product is designed to use the slope control feature of the SN65HVD234 by pulling the Rs line down with 27.4 kOhms. I've experimented with stopping CAN errors from happening by adding 100 pF in parallel with the 27.4 kOhms.
The January 2015 version of the datasheet shows a capacitor, labeled C4 in the suggested layout, in parallel with the pull down resistor, but says that it's not needed when using slope control mode. Would there be any problems expected with adding 100 pF in parallel with the 27.4 kOhms, or is that in line with recommended use? Does it make sense that a capacitor on the Rs pin would be able to fix a problem with bad packets?